Unexpected result from update query within SQL Admin / SQL Console (in SQL Project)

The best way to see this problem is to try the following in either Bungee SQL Admin or the SQL Console in a SQL project.

1) Create a table called "stuff" with two columns, "description" and "quantity":

CREATE TABLE stuff (description VARCHAR(20) NOT NULL,quantity INT NOT NULL);

Result: "0 row(s) affected"

2) Now, add data to the columns:

INSERT INTO stuff VALUES ('widget',45),('whatzit',12);

Result: "2 row(s) affected"

3) Let's see what we've created:

SELECT * FROM stuff;

The filled table columns display.

Result: "2 in result set"

Great. Now, why does the command "UPDATE stuff SET quantity=quantity+10;" return the message "0 in result set"?

UPDATE customer SET customer_id=customer_id+10;

Result: "0 in result set"

Indeed the table has been updated, which you can tell by running the "SELECT * FROM stuff" query again. So, why is the return message "0 in result set" instead of "2 row(s) affected", as was the case with the INSERT query? I'm guessing that the "result set" different from the "rows affected". Is that correct?